light feed using the common

[b21playa]

hi all

i have fitted a new light fitting in the porch and there is a wire from there to a 3 gang switch (one which will hopefully control the new light).

how can i bridge the common to supply power to the new light without going into a feed someehwere and using a junction box?

Thanks

 

[breezer]

simple, you cant. (unless there is also a neutral) see sticky for reference to see how it should be done

 

[Steve]

simple, you cant. (unless there is also a neutral) see sticky for reference to see how it should be done

to expand on this, if there are a bundle of blues or blacks connected to a terminal block, but not the switch, you have neutrals and it is possible, but if not, there are no neutrals and you need to supply your light from the ceiling.

 

[securespark]

Assuming you have a 3 plate system. If you have JB's, you may need to hunt a JB to find a neutral....

 

[Taylortwocities]

And the JB must be on the same lighting circuit. Not another lighting circuit and not another circuit (eg ring final).
If you do this its called a 'borrowed neutral' and will cause all sorts of problems either now, or in the future.

 

[securespark]

Especially if the borrowed neutral is one one side of a split board, and the live is on the other...